The present invention relates to catheter placement units and, more particularly, to an easily separable catheter-outside unit.
Catheter placement units of the catheter-outside type are well known in the prior art. Generally, they include an needle or stylet which is pointed at one end and joined to a hub at its other end and a catheter also having a hub at one end thereof. The stylet is inserted into the catheter through the catheter hub until the pointed end of the stylet extends out of the catheter at its other end and the stylet hub is connected to the catheter hub. When the catheter is to be placed into the vein of a patient, the catheter is carried into the vein by the stylet. The stylet is then removed from the catheter and an intravenous fluid infused to the patient through the catheter.
Single-handed separation of the stylet from the catheter is desirable, because it enables the person inserting the catheter to use the other hand to perform other tasks which may need to be performed during separation of the stylet from the catheter. U.S. Pat. No. 3,714,945 granted Feb. 6, 1973 to V. Stanley and entitled "Digit Manipulable Quick Release Cannula Insertion Device" discloses a catheter-outside catheter placement unit which can be separated single-handedly. U.S. Pat. No. 3,348,544 granted Oct. 24, 1967 to B. Braun and entitled "Polypropylene Cannula for Continuous Intravenous Infusion" also discloses a single-handedly separable catheter placement unit.
A disadvantage of the prior art catheters of Stanley and Braun is that their digit engageable means inherently prevent their catheters from being rotated easily when inserted in a patient. Many doctors prefer a rotatable catheter. Accordingly, it is clear that a single-handedly separable catheter-outside catheter placement unit providing a rotatable catheter when inserted would be desirable.